Hey–apparently I missed International Earthworm Day! So–here’s something wormy for you.
A lot of people don’t realize that earthworms, like their cousins the polychaete worms, also have hairs on each segment. Earthworms have tiny, hard to see bristles called setae. While you can’t see them easily, you can feel them–gently stroke a worm from tail to front, and you’ll quickly feel these little spiny setae.
Though earthworms have no bones, their segmented system of muscles enables them to alternate between being stubby and thick, and long and slender. This, in conjunction with the setae, allow the worm to anchor themselves in the dirt, either holding themselves in place (if a bird is tugging), or providing an anchor to push against as they tunnel forward.
So, why are we talking about hairy worms?
In a previous post, I linked to an illustration of a worm, and asked if it might actually be a giant phallic extraterrestrial earthworm (you’ve been warned). Someone then suggested it was more properly a Polychaete. Au Contraire! Polychaetes usually have fleshy body extensions called parapodia surrounding their hairs.
So now you know.